Railway-crossing signal



, March 4, 1930. E. WATSON RAILWAY cnossme szemn,

Filed Jan. 21 1929 'INVENTOR.

' EzP/vzsr M27150 ATTORNEY.

Patented Mar. 4, 1930 ERNEST WATSON, OF WAUWA TOSA; WISCONS RAILWAY-CROSSING SIGNAL Application filed January 21, 1929. Serial No. 334,099.

The intersecting crossings of railways by public highways are generally provided with automatically operated signals, both audible and visible, which give a warning to the traveler on the highway that a railway train is approaching the crossing. In a form of signaling device now in very common use, the parallel rails forming the track for the railway train, constitute the terminals of an open electric circuit, in whichthe signaling devices and their operating means are included. The advance of a railway train into the block in which the signaling devices are installed, serves to complete the broken electric circuit and energize the operating means for the signal through the action of the wheels and axle of a carin bridging the gap between the rails.

A railway car standing anywhere within the block, as on a siding, will complete the electric circuit and operate the signal, even though there be no train moving within the block. Thus, there will be sounded a warning the purpose of which is only to indicate the approach of a moving train. This con dition of affairs often imposes a vexatious and wholly unnecessary delay upon the movement of vehicular trafiic along the highway. And particularly is this state ofaifairs disturbing when the standing cars are so near the crossing as to interfere with a clear view of the railway tracks by the driver of the vehicle on the highway. With the signal in operation, and his view obstructed, the driver on the highway mustdelay crossing the tracks until after he has satisfied himself that the signal then in operation does not indicate the approach of a moving train. It is often'ditficult for the driver of the vehicle to do this, and unless he is fortunate enough to have a companion who can proceed to the intersection and report thatthe croing is clear, the driver is confronted by a complex situation to which it is not easy to adjust himself. If the driver be alone, he may leave his car to inspect the tracks, and reach the conclusion that the continued operation of the signal does not indicate the approach of a railway train. Finding the tracks clear, he may return to hiscar, and

proceed to cross. Meanwhile, a train may have entered the block without giving'any other warning. This very situation has actually been attended by disaster, involving the loss of human life.

The purpose of the present invention is the provision of a. signaling device, designed to be installed at the intersecting crossing of a railway by a public highway, which device is of such peculiarly novel construction that it will be operated by a locomotive. or car, or a train composed of both, only while moving within the block or operating zone of the signal, and which will be inoperative under other conditions. The presence of a car standing at or near the crossing will therefore, of itself, have no effect upon the operation of the signaling device, and consequently the cause of confusion and disaster existing heretofore, will be eliminatedrw Hence, the driver on the highway, seeking to cross at an intersection where a signaling device is installed, will be informed by the quiescent signal that the way for his passage is clear, even though his view be ob- 7 structed by standing cars.

In its preferred embodiment, the invention utilizes the disturbance of the atmosphere attendantupon the movement of a train within the vicinity of a highway crossso ing' of a railway track to influence the diaphragm of a transmitter, the vibrations of which eiiect the closing of an electric circuit and the setting in motion of the electrically actuated devices for operating the sig- 235 nal. In other words, the diaphragm is responsive to the sound waves produced by the moving train and conducted by the rails, when the train enters the block, to the transmitter by which the atmospheric vibrations are converted into electrical energy. i

In the foregoing, I have stated the genera nature and purposes of my invention. In that which follows, I shall describe the con struction and operation of the invention in a greater detail, and then point out the novelty residing in the invention in the claims appended to this specification.

In the accompanying drawing:

Figure 1 is a view from an elevation of 8.

section of railway track intersected by a highway crossing, and showing the arrangement of my invention in connection therewith;

Figure 2 is a diagrammatic view of the electrical connections.

In the drawing, the numeral 10 indicates a section of railway track of usual construction, and the numeral 11 a highwaycrossing extending thereover. The section of railway track shown is one part of a block, which comprises a like opposite section, each extending approximately the same distance from the highway crossing. It is desirable that the rails of the track within the block, be insulated at the ends of the block so as to prevent too early a transmission from distant points of the sound which is utilized to effect the operation of the signaling devices.

Attached in some convenient manner to one of the rails 12, is a sounding box 13'. Within the box is arranged a microphone 14, provided with a diaphragm which will vibrate in response to pulsations of the atmosphere, produced by the sound generated by a railway train moving within the block. Vibration of the diaphragm effects a contact with the terminals of an open electric circuit 15, and serves to complete such electric circuit. A relay 16 is included in the circuit 15, which, when closed,'permits a flow of current which energizes .the coil of the relay, so as to give an axial movement to the core of the said coil. An amplifier of suitable construction and capacity should be arranged within the sounding box 13, or conveniently associated with the circuit 15. In the movement of the core of the coil, the armature 17 is brought into contact with the terminals 18 and 19 of an openelectric powercircuit 20, and the contact thus established acts to close the said power circuit. The circuit 20 includes the signaling devices 21, which may comprise a semaphore or other visible signal, and a hell or other audible signal. The signaling devices should show a red light at all times during operation, and the power circuit 20 should include an electric motor for actuating the moving mechanical parts necessary in the operation of the signaling devices.

In operation, when a moving train enters either end of the block extending at both sides of the highway crossing, the sound created by the moving train will be transmitted through the rail to the sounding box and to the microphone. The diaphragm of the latter being responsive to the vibrations produced by the sound waves will close the electric circuit, and through the connections and means described, effect the operation of the signaling devices.

The invention is not limited to the uses described, but may be utilized to effect the actuation of gates to gua d the crossing as although the rails may be brought into electrical connection by the wheels and axle of a car standing on a siding near the highway crossing, the signaling device will not be operated until after a train has entered the block, and the sound produced by themovement of the train has caused the diaphragm to close the open circuit. Whereupon, the circuit including the rails is closed by the action of the relay, and the signaling devices will be operated as described.

Moreover, the visible signal may be in any desired form, and I'include as within my invention, a construction in which a flood of light may be caused to brightly illuminate the crossing while a train is moving through the block.

Having thus described my invention, what I claim and desire to secure by Letters Patent of the United States, is:

1. In a signaling device for railway crossings, a signal, an electric circuit and means therein for actuating the signal, and a trans mitter associated with one of the track rails and having a. diaphragm responsive to the sound produced by a train moving over the rails to close the circuit and actuate the signal.

2. In a signaling device for railway crossings, an electrically operated signal, and means associated with one of the track rails responsive to the sound produced by a train -moving over .the rails to close an electric circuit and actuate the signal.

3. In a signaling device for railway crossings, a signal, an electric circuit and means therein for actuating the signal, a sounding box associated with one of the track rails, and means within the said box responsive to the sound produced by a train moving over the rails to close the said circuit and energize the actuating means for the signal.

4. In a signaling device for railway crossings, a-microphone associated with one of the track rails and having a diaphragm responsive to the sound produced by-a train moving over the rails, an electric circuit adapted to be closed by vibrations of the diaphragm of the microphone, a signal and an open electric power circuit therefor, and a relay in the first mentioned circuit adapted to close the .power circuit to actuate the signal when the a signaling device, a sounding box associated with one of the rails and containing a, microphone having a diaphragm responsive to sound produced by a train moving over the track, a signal, an electric circuit and means therein for actuating the signal, and means operated by the vibrations of the diaphragm for closing thecircuit and energizing the ac tuating means for the signal.

6. In a signaling device for railway crossings, a signal, electrically operated means for actuating the signal and a microphone associated therewith responsive to the sound produced by a moving railway train to close an electric circuit and energize the actuating means for the signal.

In testimony whereof, I have si ed my name at Milwaukee, this 12th day of anuary,

1929. ERNEST ,WATSON. 

